previous changing of variable names caused an error in the program logic.

Caused when creating LoadLanguageOptions().

Accidentally commented out in ac82698f.

Loading Voice and Language options is complicated. They are not
separated in the code.

This PR creates langopts.c for holding language option related
configuration. In the future:
1. all new language options should go to langopts.c
2. voice options should have a similar file
3. LoadVoice should know if it's loading a voice or a language.

These have no tests and should be refactore to be similar to other
langopts.

Note: This feature has no tests.

Note: This feature has no tests. It doesn't look very useful and I think
could be removed.

We currently have two switch statements. Every key should go to only one
of them.

The switch case in LoadVoice() currently mixes voice and language
options. This change will start separating them into two functions.

CheckTranslator will be moved to langopts.c. In the future there should
be no need to use it in voices.c. There will be other temporary
solutions also.

This removes these words from dictionary and uses translation rules
instead. Result is to shorten the i.

See #1337 and #1388.

1. Rewrite cmn_rules. Vowel will be spoken as Mandarin only when it's
with a tone number. Otherwise, it will be regarded as English. This will
make English words translated more correctly.
2. Fix issue of word item in cmn_listx not taking effect.
3. Fix dictionary_skipwords bug. It should be injected when re-structing
method TranslateWord3.

See #1388 and #875.

Add some rules and exceptions for italian language.

Closes #1194.

Windows: add mto dict

Russian: improve numbers and add words

Code cleanup: relocate functions & remove unused #defines